The present invention relates to movable weighted bases used to support objects such as large umbrellas, lighting assemblies, lamps, TV monitors, music speakers, laundry hangers, Christmas trees, etc. and to facilitate transportation of these objects along hard surfaces such as concrete, stone, brick or hardwood floors.
Large umbrellas are often used outdoors in places such as backyards, restaurants and public pools, where they are placed on a hard surface and supported by a stationary weighted base. The base is normally formed of concrete, metal or a hollow plastic enclosure filled with a material that imparts weight, for example water, sand, or rock. The base is provided with a circular socket that receives a vertical shaft of the umbrella. A large umbrella, with a canopy diameter that can reach 2-4 meters, needs a heavy base for support, particularly in windy conditions. The base may weigh many tens of kilograms, and is often too heavy to be moved by one person. Obviously, moving around the umbrella and the base together is even more difficult. Solutions to this problem often include improvised ways such as wiggling the umbrella and base in a pendulum motion while pulling it across the surface, or using two persons to carry it from place to place.
Lighting assemblies, such as those used in television studios have a different problem. The assemblies include a vertical pole connected to a base, for example a tripod base. Although the assembly itself is not normally too heavy, it has to be extremely stable in use, and often the base cannot supply the required stability. In such cases, sandbags hanged on horizontal members connected to the pole often weigh down the lighting assembly. This is a cumbersome operation, with the sandbags often carried separately when the assembly is moved.
Moveable bases which support umbrellas, lamps, lighting or other objects connected to the base by a vertical shaft are known in the art. Examples include the extension lamp support of U.S. Pat. No. 2,479,720 to Brandt, and the movable umbrella of U.S. Pat. No. 5,957,145 to Plumer. These prior art bases are based on wheeled devices, in which the wheels do not provide the stabilizing weight. The wheels are normally part of a more complex structure, which, as in the case of U.S. Pat. 5,957,145 includes a stabilizing frame and a carrying handle. In contrast with the present invention, these prior art bases do not combine compactness, weight, stability and full 360 degrees movement capability along the underlying surface.
Rolling elements such as ball transfer units are well known in the art. These elements are normally used in loading systems, conveyor platforms for moving cargo, etc. The balls in these ball transfer units do not function as principal weight elements, and do not serve as the stabilizing structure itself.
There is thus a widely recognized need for, and it would be highly advantageous to have, a movable weighted base that is simple to manufacture and assemble, easy to operate, compact, and stable.
The present invention relates to movable weighted bases such as those used to hold and support large umbrellas on hard surfaces such as concrete floors. Particularly, the present invention discloses a rolling weighted base, in which spherical rolling elements, similar in principle to ball transfer units, provide the bulk of the base weight. The rolling weighted base of the present invention is compact and stable, has full 360xc2x0 movement capability along the surface, and is configured to receive a vertical shaft of objects such as a large umbrella, a heavy lighting or lamp stand, etc. The base of the present invention is particularly useful for supporting such objects in their normal use, and for easily moving such objects around on hard surfaces, obviating the need for lifting and carrying the objects. The specification refers hereafter to xe2x80x9cumbrellasxe2x80x9d as exemplary objects that can be supported and moved around on a hard surface by the weighted base of the present invention. However, the disclosed rolling weighted base is obviously useful for supporting and moving around any object supported by a vertical shaft, in particular objects such as lighting assemblies, lamps, TV monitors, music speakers, laundry hangers, and Christmas trees.
According to the present invention there is provided a rolling weighted base for supporting an object and for facilitating the movement of the object along a hard surface, the base connected to the object by a vertical shaft, the base having a total weight, the base comprising: a) at least three weight balls having a combined weight greater than half the total base weight; and b) a housing configured to receive the vertical shaft and to hold the at least three balls rigidly spaced apart so that the at least three balls do not touch each other, the at least three balls partially protruding from the housing toward the hard surface, the at least three balls free to rotate inside the housing.
According to a further feature of the present invention, the housing includes individual housing units for each of the at least three weight balls.
According to a further feature of the present invention, the at least three balls are of equal size.
According to a further feature of the present invention, the at least three balls are spaced apart at an equal angle to each other.
According to a further feature of the present invention, the configuration of the housing to receive the vertical shaft includes a socket
According to a further feature of the present invention, the housing is configured to support an object chosen from the group consisting of an umbrella, a lighting assembly, a lamp, a TV monitor, a music speaker, a laundry hanger and a Christmas tree.
According to a further feature of the present invention, the weight balls include bowling type balls.
According to a further feature of the present invention, the free rotation of the at least three balls inside the housing is facilitated by ball bearings.
According to a further feature of the present invention, the base further comprises means for quick assembly and disassembly of the individual housings.
The present invention successfully addresses the shortcomings of the presently known configurations by providing a rolling weighted base which is simple to manufacture and assemble, easy to operate, compact, and stable